Vehicle remote starters are a common and valuable possession for many vehicle owners. The remote starter system allows the vehicle owner that lives in a climate that is unusually warm or cold to start their engine for a predetermined amount of time and allow the vehicle interior temperature to stabilize to a comfortable level. Vehicle remote starters historically consisted of an electronics module that connects into the vehicle at various points and controls various vehicle functions by applying voltage to discrete wires to control various aspects of the vehicle operation. For example, a wire might be connected to the heater or air conditioning supply line and when voltage is applied the heater or air conditioning unit will activate and begin to climate control the vehicle interior. Furthermore, the majority of vehicles produced after the model year 1995 incorporate an additional security measure known as an immobilizer. The immobilizer is a system that is comprised of a small cryptographic controller built into the vehicle key and an electronic reader that is built into the vehicle key cylinder. The purpose of the immobilizer system is to create an additional layer of vehicle security above the physical key by requiring that the vehicle electronic systems verify that the correct vehicle key is present and authorized via an electronic keycode exchange.
The installation of the remote starter is typically performed by a technician that routes the individual wires from the remote starter module to each target wire that corresponds to a circuit in the vehicle that requires control. These wires are then connected to the target circuit using a variety of methods, but most typically the process used is to remove a small section of the insulation covering the wire and then soldering the remote starter wire to the target wire using heat and a lead based solder. Additionally the vehicle immobilizer system is bypassed by means of physically placing either an authorized vehicle key which contains the aforementioned cryptographic controller inside the vehicle or by placing an additional authorized cryptographic controller inside the vehicle. The cryptographic controller is electrically coupled to the electronic reader in the vehicle key cylinder such that when the engine is commanded to start with the remote starter system, the cryptographic controller will present a valid keycode to the vehicle electronic systems which in turn allow the engine to start.
The remote starter system described above exhibits two deficiencies that prevent its use in many modern vehicles. The first deficiency relates to the proliferation of electronic networks in modern vehicles: A modern vehicle dispenses with the discreet wiring previously described and instead uses serial data lines to convey data and changes in the vehicle state to other parts of the vehicle. A serial data line is a single or multiple wire connection that presents information as a series of voltage pulses related by time. Common types of vehicle serial data protocols are canbus, flexray, most, linbus, and rs232. For example, in the prior art description the heater or air conditioning system, engine, starter, and accessories circuits each had a single discrete wire that convey data by simply changing voltage state: The presence of voltage on the wire would indicate that the circuit was active. A vehicle with a serial data system will instead combine or multiplex those signals, each conveying a different vehicle state or item of data along with hundreds or even thousands of other signals onto one or two wires. Newer vehicles utilize a system comprised of many electronic controllers interconnected using one or more vehicle networks. Such a system will include an electronic ignition module which relates changes in the vehicle operating state, an electronic engine controller, which controls the engine operation as well as other controllers which control the state of the vehicle transmission, the heater, air conditioning, and other systems. Any change in vehicle state (for example to start and run the vehicle engine) is coded as data which is transmitted across the vehicle network. This modern networked vehicle can no longer use the older discretely wired remote starter systems but rather require a new type of remote starter system which actuates any change in vehicle state by directly modifying data which is normally passed along the vehicle network. While some prior art exists relating to reading or writing data items on the vehicle network for the purpose of implementing a vehicle remote starter, this is deficient for the purposes of the stated invention as existing data which is sent between various modules on the network must actually be filtered and modified. All prior art lacks this ability as the described systems only connect to the network but lack the ability to filter or modify existing data.
The second deficiency relates to the required placement in the vehicle of a dedicated cryptographic controller as part of the immobilizer system. This requirement creates both economic and security impracticalities in that the cryptographic controller is typically expensive and the vehicle owner must either supply or purchase the controller which must the permanently reside in the vehicle to allow the engine to be remote started. Since the cryptographic controller always remains in the vehicle, a security risk is also created as a thief given the information that the vehicle has a remote starter system installed knows that the vehicle immobilizer system can be defeated simply by locating the cryptographic controller that must be located somewhere in the vehicle.